1. Field of the Invention
The present invention generally relates to a liquid crystal display (LCD), and more particularly to a system and method of controlling halt and resumption of scanning actions of an LCD.
2. Description of Related Art
Liquid crystal display (LCD) technology has been widely used in television sets and a variety of other electronic devices. According to specific characteristics of liquid crystal molecules, a polarity inversion scheme is commonly applied to change the direction of electric field at regular intervals such as frame, column, row or dot, such that the polarity of the electric field changes every frame, column, row or dot. FIG. 1 shows two neighboring frames for which row inversion scheme is utilized. In frame N, the polarity of the first row is positive “+”, and the polarity of the second row is changed to negative “−”, and so on. In frame N+1, however, the polarity of the first row is negative “−”, which is the inverse of the polarity of the same row in the preceding frame N.
Television broadcasting, and electrical communication in general, is commonly subject to noise or disturbance. An LCD television set that receives such noise may cause annoyance to viewers. FIG. 2 shows an example in which frame N suffers noise beginning at the fourth row, and therefore display of the remaining rows is stopped. After recovering from the interruption, frame N+1 starts the display from the first row. It is noted that the last display row (i.e., the third row) in frame N and the continuing row (i.e., the fourth row) in frame N+1 has the same polarity “+”. Consequently, this situation, as indicated by the arrow in the figure, may cause flicker to viewers.
For the reason that conventional LCDs cannot effectively recover from an inevitable interruption caused, for example, by noise, a need has arisen to propose a novel scheme that may avoid flicker or other annoyance induced during the recovery from display interruption.